1. Field of the Invention:
The invention pertains generally to the art of robotics and in particular to that part of the art which pertains to multi-axis wrist designs.
2. Description of the Prior Art:
The closest prior art of which I am aware is found in U.S. Pat. No. 4,068,536 which discloses a wrist of the type which I call a split-ball type, and in which a first portion of the ball is rotatable about one axis, while a second portion of the ball is rotatable relative to the first portion about another axis, and the end effector carried by the second portion of the ball is rotatable about its axis. As is stated in connection with the ability of the device of that patent to perform, such a device generates an imaginary spherical sector as it is rotated through space, is capable of orientating a part normal to any point on the generated spherical sector and with this capability thus eliminates "holes" or "voids" in the spatial orientation of the end effector and increases the manipulator's flexibility.
A split-ball type wrist and manipulator assembly according to my invention has the same capability in a three-axis form and, further, in both its two and three-axis form is considered to have advantages in its construction and in particular with respect to the construction permitting the running of power line means such as electrical cables and air hoses completely internally through the arm and through the wrist to the end effector.